The present invention relates to food products and to their methods of preparation. In particular, the present invention relates to food products prepared from a cooked cereal dough, especially ready-to-eat cereals and to their methods of preparation.
A wide variety of food products are prepared from cooked cereal doughs especially ready-to-eat (“R-T-E”) or breakfast cereals, as well as a variety of snack products. Generally in the preparation of the cooked cereal dough, cereal or farinaceous ingredients such as various cereal flours are first admixed with other dry ingredients such as salt, minerals, starch, sugars, to form a dry blend of ingredients and then is further blended with various liquid ingredients, including moisture and heated to gelatinize or cook the starch fraction of the cereal ingredients and other starchy materials. The gelatinized or cooked mass is then worked to form a cooked cereal dough. A wide variety of blending cooking, working apparatus and techniques are well known. More recently, the preparation of a cooked cereal dough using a cooker extruder especially a twin screw extruder has become commonplace. The cooked cereal doughs so prepared can be processed to form finished products of various size, textures, and shapes. Typically, the post, cooked cereal dough formation step involves forming suitably sized and shaped individual pieces and drying to form finished cereal base pieces such as shreds, flakes, biscuits or puffs. Thereafter, the finished dried cereal base pieces can have a topical coating applied to provide desired taste and texture attributes. For example, in the preparation of a breakfast cereal, the topical coating can include a sugar coating. In other variations, such as for seasoned snack products, the topical coating can include salt alone or in combination with various seasoning blends.
Frequently the blend of ingredients from which the cooked cereal dough is prepared can include low levels of an added fat ingredient. Added fat is to be distinguished from native levels of fat provided by employment of any other ingredient especially the native fat associated with the employment of whole grain cereal ingredients or flours. Inclusion of fats can be made as a processing aid to facilitate the mixing of the ingredients, or to improve the workability of the cooked cereal dough such as in a cooker extruder, or to control or limit the degree of expansion of the cooked cereal dough when used to prepare puffed cooked cereal dough pieces. Generally, the fat is added at low usage levels; typically about 3% or less. Since the finished dried cooked cereal dough cereal pieces are generally used to prepare shelf stable finished food products that are intended to be stored at room temperatures for extended times, these processing aid fat ingredients typically were provided in the form of at least partially hydrogenated fats in order to reduce rancidification of the fat ingredient over extended storage times. While extremely useful, and of widespread employment for decades, current health and nutrition trends disfavor employment of hydrogenated fats since such fats often contribute undesirable trans fatty acids.
While non hydrogenated liquid oils such as common commodity oil types e.g. soybean oil, corn oil, canola oil can be used as processing aids, the resultant finished products can exhibit greater degrees of and faster rates of product rancidification due to the absence of hydrogenation and/or the greater degree of unsaturation.
One technique to minimize the rancidification potential of employing non hydrogenated fats or oils is to add antioxidants or preservatives such as vitamin E, BHA (Butylated hydroxyanisole), BHT (butylated hydroxytoluene), TBHQ (Tert-Butyl Hydroquinone), that are known to reduce rancidification rates. While useful, to be most effective, such materials need to be added after any heating step since exposure to harsh temperature conditions can lead to rapid loss of the preservative. However, cooked cereal dough preparation generally requires at least some heat exposure (to gelatinize the starch fraction) and often the heating and cooking step can be prolonged (for up to several hours). Even post cooking steps such as puffing, drying or application of a topical coating, e.g., sugar, involves one or more steps that involve heat exposure. Such heating can result in significant or even substantially total loss of the preservative in the finished cooked cereal dough product.
Another approach to avoid the problems of undesirably rapid rancidification is to employ a specialty oil that is naturally resistant to rancidification such as a high oleic fatty acid oil. While useful to mitigate the degree and rate of rancidification, such specialty oil ingredients command premium prices and are subject to limitations on sourcing and usage.
An additional consideration for commercial preparation of breakfast cereals is that the sourcing of high oleic oil is not without some risk. The feedstock for such specialty oils are grown in only narrow climatic zones especially in Canada and the Northern United States. Thus, this ingredient supply is subject to a higher level of weather related availability risk.
Surprisingly, it has been found that rice bran oil can be used as a processing aid ingredient in the preparation of cooked cereal doughs and finished food products prepared there from. It has been more surprisingly been discovered that high oryzanol rice bran oil is particularly effective at providing the desirable functionality of a fat cereal dough preparation processing aid; is surprisingly resistant to rancidification in finished food products prepared from cooked cereal doughs even when stored at room temperatures for extended periods. Notwithstanding the surprising resistance to rancidification, the high oryzanol rice bran oil nonetheless, desirably provides levels of trans fatty acids. Moreover, high oryzanol rice bran oil is commercially available in commercial quantities at competitive pricing.
The present invention is thus directed towards formulating cooked cereal doughs with a reduced cost non hydrogenated oil ingredient that provides comparable levels of resistance to rancidification in cooked cereal dough products to the rancidification of such specialty oil ingredients and superior to that of commodity oil ingredients.